Cut squash in half lengthwise, and remove seeds. Place cut side down in a greased baking dish; add 1/2 inch water. Cover and bake at 350 degrees F for 30 minutes. Melt butter in a small saucepan. Add celery and onion; cook until tender. Add ham, sugar, and allspice; stir well. Cook over medium heat until thoroughly heated. Stuff squash with ham mixture. Cover and bake at 350 degrees F for 15 minutes. Remove cover, and bake an additional 15 minutes. Yield: 4 servings. Mrs. James Barden of Virginia in October, 1981 "Southern Living" Typos by Jeff Pruett